Allocation, as you have done it, is a recurrent discussion issue that is better approached by writing a short test stub to do nothing except the allocation and just see what happens.

I wrote a program recently to test such a thing, ran through five or ten loops before the memory issue slowed things down. Start with 1024 x 64 or something, I would not think a [1024][1024] to be too far from blowout, but we have to realize that the two numerics multiply as a [][]